Commonly, angles of a headrest of a sofa can be adjusted to meet the requirement of the customers. One of the new achievement manners is to set a hinge connected with the headrest in the seat or sofa, and the angle of the headrest is changed when the headrest is pivoted together with the hinge. As such, the customer can adjust the tilting angle of the headrest according to his actual requirement to obtain a comfortable feeling. However, this adjusting manner must require a manual operation to pull the headrest, which brings an inconvenient operation. In order to adjust the angle of the headrest conveniently, the hinge in the seat or sofa is replaced with an electric headrest support system, an upper end of the headrest support system is fixed to the headrest, and the angle of the headrest can be adjusted automatically by a motor without manual operation.
However, the conventional headrest support system just can be applied to a one-piece sofa that the headrest support system thereof can not be separated from the sofa body after being installed, while actually, most headrest support systems of sofas are configured to be detachable to facilitate cleaning or replacement.
Thus it's necessary to provide a headrest support system for automatically adjusting a tilting angle of a sofa headrest and being installed in a detachable sofa.